Do not emit a UsedDirective for things in the llvm.used
list that have internal linkage; the linker doesn't need
or want this. (These objects must still be preserved
at compile time, so just removing them from the llvm.used
list doesn't work.) Should affect only Darwin.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55722 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index dc88da9..a720f04 100644
--- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -425,8 +425,34 @@
return false;
}
+/// findGlobalValue - if CV is an expression equivalent to a single
+/// global value, return that value.
+const GlobalValue * AsmPrinter::findGlobalValue(const Constant *CV) {
+ if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
+ return GV;
+ else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
+ const TargetData *TD = TM.getTargetData();
+ unsigned Opcode = CE->getOpcode();
+ switch (Opcode) {
+ case Instruction::GetElementPtr: {
+ const Constant *ptrVal = CE->getOperand(0);
+ SmallVector<Value*, 8> idxVec(CE->op_begin()+1, CE->op_end());
+ if (TD->getIndexedOffset(ptrVal->getType(), &idxVec[0], idxVec.size()))
+ return 0;
+ return findGlobalValue(ptrVal);
+ }
+ case Instruction::BitCast:
+ return findGlobalValue(CE->getOperand(0));
+ default:
+ return 0;
+ }
+ }
+ return 0;
+}
+
/// EmitLLVMUsedList - For targets that define a TAI::UsedDirective, mark each
/// global in the specified llvm.used list as being used with this directive.
+/// Non-globals (i.e. internal linkage) should not be emitted.
void AsmPrinter::EmitLLVMUsedList(Constant *List) {
const char *Directive = TAI->getUsedDirective();
@@ -435,9 +461,12 @@
if (InitList == 0) return;
for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
- O << Directive;
- EmitConstantValueOnly(InitList->getOperand(i));
- O << '\n';
+ const GlobalValue *GV = findGlobalValue(InitList->getOperand(i));
+ if (GV && !GV->hasInternalLinkage()) {
+ O << Directive;
+ EmitConstantValueOnly(InitList->getOperand(i));
+ O << '\n';
+ }
}
}